Tributyltin Chloride → HCID 71280194, compound

Temperature

-15 °C

To a solution of 3-iodo-1-methyl-1H-thieno[3,2-c]pyrazole (290 mg, 1.10 mmol) in THF (6 mL) at −15° C. was slowly added isopropylmagnesium chloride (2.0 M in THF, 0.66 mL, 1.32 mmol). The bright yellow heterogeneous reaction mixture was stirred at −15° C. for 20 min then tributylchlorostannane (0.36 mL, 1.32 mmol) was added dropwise. Stirring was continued at −15° C. for 20 min then at room temperature for 2 h. The reaction mixture was quenched with water and extracted with EtOAc (2×). The combined organics were washed with brine then dried over MgSO4 and concentrated. The residue was purified by silica gel chromatography with 10% to 20% EtOAc/heptane (0.5% Et3N) gave 298 mg (63%) of 1-methyl-3-tributylstannanyl-1H-thieno[3,2-c]pyrazole as a pale yellow oil. 1H NMR (CDCl3, 300 MHz): δ (ppm) 7.36 (d, J=5.3 Hz, 1H), 6.90 (d, J=5.3 Hz, 1H), 4.06 (s, 3H), 1.54-1.67 (m, 6H), 1.36 (dq, J=14.7, 7.3 Hz, 6H), 1.13-1.22 (m, 6H), 0.90 (t, J=7.3 Hz, 9H).

1. customat −15° C.
2. stirringStirring
3. waitwas continued at −15° C. for 20 min
4. waitat room temperature for 2 h
5. customThe reaction mixture was quenched with water
6. extractionextracted with EtOAc (2×)
7. washThe combined organics were washed with brine
8. dry with materialthen dried over MgSO4
9. concentrationconcentrated
10. customThe residue was purified by silica gel chromatography with 10% to 20% EtOAc/heptane (0.5% Et3N)

ORD record

ord-61601296bac445639b6498666b3ccc40

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08658646B2